Oxidative Stress: Cause and Consequence of Diseases

The Chemoprevention of Chronic Degenerative Disease Through Dietary Antioxidants: Progress, Promise and Evidences

“…Different researches indicate that mutations produced in genes are responsible of the metabolic unbalance of ROS, while others suggest that environmental changes and common habits weigh on human metabolic processes. However, doubt remains, if oxidative stress is the primary event that leads to the disease or the oxidative phenomenon is developed throughout the disease [22].…”

“…As a rule, genetic polymorphisms of enzymes may lead to oxidative stress and consequent diseases, among which cancer, neurodegeneration, cardiovascular disorders, and diabetes are most frequently mentioned. Among the most studied enzymes with genetic polymorphism is the glucose-6-phosphate dehydrogenase, catalase, superoxide dismutase, glutathione peroxidase and those involved in reparation of oxidized molecules and the disease progression [22].…”

Underinvestigated Roles of Glucose-6-Phosphate Dehydrogenase

“…This gene encodes an AAA family ATP-ase which is responsible for insertion of Rieske Fe/S center into the complex III [47]. Production of ROS can also be enhanced via disturbances in iron homeostasis since iron is a reactant in Fenton reaction, in which hydroxyl radical is formed from hydrogen peroxide [14,39]. Interestingly, Fe/S clusters of the complex I themselves are sites of ROS production [44].…”

“…This step integrates production of ribose-5-phosphate in PPP and ribonucleotide biosynthesis with production of NADPH in PPP and deoxyribonucleotide biosynthesis. Reduced glutaredoxins are necessary for the assembly of Fe/S clusters and heme synthesis [14,68] as it was mentioned above for NADPH. These roles of NADPH and reduced thiol-containing compounds may also partially explain development of hemolytic anemia in response to certain drugs for people with G6PDH deficiency that will be examined in more details in the review.…”

“…This compound is an essential reductant used in numerous biosynthetic processes [48]. Particularly, NADPH takes part in fatty acid and sterol synthesis, reduction of low and high molecular mass thiols [48], and consequently, in synthesis of heme and assembly iron-sulfur (Fe/S) clusters [14,68]. These roles for NADPH, which is reduced mainly by G6PDH, characterize the latter as lipogenic and related to antioxidant defense enzyme.…”